Neisseria Meningitidis Invasion Assay
Neisseria Meningitidis Invasion Assay - Related Videos
12:58
Visualisation and Quantification of Intracellular Interactions of Neisseria meningitidis and Human α-actinin by Confocal Imaging
0 Views •
2010
Neisseria meningitidis (Nm), a gram negative human-specific respiratory pathogen, can bind to human α-actinin. Here we present a protocol for visualisation of colocalisation of the bacterium with intracellular α-actinin after bacterial entry into human brain microvascular endothelial cells (HBMECs).
10:12
Neisseria meningitidis Infection of Induced Pluripotent Stem-Cell Derived Brain Endothelial Cells
0 Views •
Cited by 11 •
2020
The protocol described here highlights the major steps in the differentiating induced pluripotent stem-cell derived brain-like endothelial cells, the preparation of Neisseria meningitidis for infection, and sample collection for other molecular analyses.
02:45
Culturing Neisseria gonorrhoeae in Metal-Depleted Conditions
0 Views •
2025
Source: Maurakis, S., and Cornelissen, C. N. Metal-Limited Growth of Neisseria gonorrhoeae for Characterization of Metal-Responsive Genes and Metal Acquisition from Host Ligands. J. Vis. Exp. (2020)This video demonstrates the procedure for growing Neisseria gonorrhoeae under metal-limited conditions using a defined, metal-depleted medium.
07:58
Invasion Assay Using 3D Matrices
0 Views •
2023
The extracellular matrix (ECM) is a network of molecules that provide a structural framework for cells and tissues and helps facilitate intercellular communication. Three-dimensional cell culture techniques have been developed to more accurately model this extracellular environment for in vitro study. While many cell processes during migration through 3D matrices are similar to those required for movement across rigid 2D surfaces, including adherence, migration through ECM also requires cells...
07:53
An In vitro FluoroBlok Tumor Invasion Assay
0 Views •
Cited by 23 •
2009
This video demonstrates how to measure cell invasion through cell culture inserts using a fluorescence-based methodology.
FAQs
Gentamicin is added after host cells have been exposed to Neisseria meningitidis. The antibiotic eliminates organisms remaining outside the cells, while bacteria that have entered host cells can subsequently be released and quantified. The resulting colony count therefore provides a readout of viable intracellular meningococci under the tested host-cell and bacterial conditions.
The invasion assay primarily quantifies bacteria that remain recoverable after extracellular organisms have been eliminated, so its strongest readout concerns internalization and intracellular survival. Attachment contributes to the opportunity for entry but is not necessarily measured independently. Comparing assay conditions or bacterial variants can help identify factors associated with adhesion, entry, or both.
Bacterial strain, host-cell condition, and targeted bacterial genetic mutations can all influence the number of organisms recovered. These comparisons help reveal whether particular meningococcal features or cellular environments favor adhesion, internalization, or survival after entry. Interpreting results requires keeping the comparison focused on the specific strain, host condition, or mutation being evaluated.
The workflow begins by culturing epithelial or endothelial host cells and exposing them to meningococci. After the interaction period, gentamicin is applied to remove extracellular bacteria. Host-cell-associated intracellular organisms are then released, and the recovered bacteria are quantified by colony counting. Results are compared across strains, mutants, or host-cell conditions.
Colony counting reports the number of viable meningococci recovered from within the host-cell system after extracellular bacteria have been removed. Higher or lower counts indicate differences in the combined outcome of bacterial entry and survival under the selected conditions. The measurement is especially useful for comparing strains, genetic mutants, or altered host-cell environments.
This method is useful when investigators need to examine meningococcal pathogenesis at the host-cell interface. It supports studies of host–pathogen interactions and helps evaluate bacterial factors that contribute to invasive disease. The same comparison framework can also be applied when assessing potential antimicrobial or preventive strategies that alter bacterial entry or intracellular recovery.